Candy Cummings had a brief but influential career. From 1872 to 1877, he compiled a 145-94 career record and 2.49 ERA while playing for five different teams. He is credited with being the first pitcher to throw a curveball, which he first threw at a game in Worcester, MA while playing for the Brooklyn Stars, a non-major league team. However, some historians dispute this claim.

Cummings issued only four bases on balls in 416 innings in 1875. His 82 strikeouts led the league that season, and his 20.5-1 strikeouts-to-walks ratio is the best mark of all time for anyone with 80+ innings pitched.

Cummings became interested in the curve ball around 1863, and later pitched for several years for the junior and then varsity team of the amateur Brooklyn Stars. Even after the National Association started in 1871, Cummings stayed with the Stars, but joined the National Association in 1872.

"I asked Start if there was any doubt about Arthur Cummings being the inventor of curve pitching. 'No doubt whatever', said he, warming up to the subject. 'I remember all about the circumstance, as I was brought up in Brooklyn, and was playing around the same lots with Cummings from 1866 to '70. Cummings was the first to get the curve . . . Cummings was fooling the boys with a perfect curve long before any other pitcher could get it." - Tim Murnane's interview of Joe Start, published in Sporting Life, Nov. 16, 1895